An unconventional exorcist (Aaron Eckhart) must use his psychic abilities to do battle with a malevolent demon that has taken over an innocent 11-year-old boy (David Mazouz). But he discovers he's up against a more formidable foe than he anticipated when it's revealed that the same malicious entity previously murdered his wife and child. Now, he's in a race against time to defeat his worst enemy before it unleashes its wrath upon the entire world. Carice van Houten co-stars.